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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">David<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">KC never finished work on this stuff. I’m copying him because I’m sure he’d be happy to help.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">KC: can you summarise where you left it?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">I think it’s very interesting work, and has the potential to make GHC’s RTS much more malleable, by moving more of it into Haskell libraries instead of deeply-magic C code.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">But it’s not easy, because we are reluctant to lose performance, and because there are interactions with STM, weak pointers, foreign function calls, etc. I think it’d require a bit of commitment
to make a go of it.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> ghc-devs [mailto:ghc-devs-bounces@haskell.org]
<b>On Behalf Of </b>Daniel Bennet<br>
<b>Sent:</b> 28 December 2016 17:23<br>
<b>To:</b> ghc-devs@haskell.org<br>
<b>Subject:</b> Lightweight Concurrency Branch<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The lightweight concurrency branch is highly interesting and relevant to my interests, however, the ghc-lwc2 branch hasn't been updated in several years even though it's listed as an active branch at
<a href="https://ghc.haskell.org/trac/ghc/wiki/ActiveBranches">https://ghc.haskell.org/trac/ghc/wiki/ActiveBranches</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The wiki page for the work hasn't been updated in almost two years either,
<a href="https://ghc.haskell.org/trac/ghc/wiki/LightweightConcurrency">https://ghc.haskell.org/trac/ghc/wiki/LightweightConcurrency</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Relevant papers:<o:p></o:p></p>
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<p class="MsoNormal">Composable Scheduler Activations for Haskell (2014)<o:p></o:p></p>
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<p class="MsoNormal"><a href="https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Ftimharris.uk%2Fpapers%2F2014-composable-tr.pdf&data=02%7C01%7Csimonpj%40microsoft.com%7Cd132a48641a54f732ffc08d42f463e8b%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C1%7C636185426136080161&sdata=YG%2B0xfi%2Bd74Vi9GBI8iTrr4GEMzjS2WwrI182%2BcEgqM%3D&reserved=0">https://timharris.uk/papers/2014-composable-tr.pdf</a> <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Composable Scheduler Activations for Haskell (2016)<o:p></o:p></p>
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<p class="MsoNormal"><a href="https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fkcsrk.info%2Fpapers%2Fschedact_jfp16.pdf&data=02%7C01%7Csimonpj%40microsoft.com%7Cd132a48641a54f732ffc08d42f463e8b%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C1%7C636185426136080161&sdata=mH79Y3U%2BdDvcw2PA8lGcFaPMJw6DgCIXbu%2F3WGvyGaU%3D&reserved=0">http://kcsrk.info/papers/schedact_jfp16.pdf</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">What remains for integrating this branch into GHC?<o:p></o:p></p>
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